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33 个结果
  • 简介:WetheoreticallyinvestigatednegativeentropySofbiopolymerwhichpassesthroughananometerpore(suchasα-hemolysin),especiallyenteringprocessandescapingprocess,onthebasisofwhichwealsostudiedbiopolymerentering-poretimeτent,biopolymerenteringmeanvelocityvent,biopolymerescaping-poretimeτesc,andbiopolymerescapingmeanvelocityvesc,respectively.Ourresultsillustratethattheenteringandescapingprocessesofbiopolymerdependonitsnegativeentropy,andenteringprocessismoredifficultthanescapingprocessforbiopolymertranslocation.Thistremendousdifferencebetweenthetwoprocesseswillofferausefulengineeringhintforsinglemacromoleculeidentification.

  • 标签: 纳米孔 生物高分子 生物聚合物 逃逸 生物大分子 平均流速
  • 简介:Thispaperproposesanautomaticmethodofporecombinationrecognition,whichisanimportantfeaturetohardwoodrecognition.Afterextractingedgefromwoodmicroscopiccross-section,basedonareahistogramofthesimilarcircleregions,themethodclassifiesallregionsintotwoclasseswithmaximumbetween-classvariance,soastodistinguishtheporefromothertextures,whicharesimilarinshapesbutdifferentinsizes.Meanwhile,secondobjectivefunctionaboutaverageareaofclosedregionsisusedtoimprovetheporesegmentationperformance.Atlast,themethodusesadjacencydegreeofporesettojudgeporecombination.Theexperimentsdemonstratethatthetaskofporesegmentationcanbecompletedsuccessfullyforallkindsofporedistributionandcombination,andalsothecorrectcombinationsofporesaregiven.

  • 标签: ADJACENCY degree of PORE set MULTI-OBJECTIVE
  • 简介:DuringthereactionbetweencalciumsorbentsandSO2,calciumsorbentsarefirstcalcinedandconvertedintoCaO.CaOcanbeobtainedbycalciningCa(OH)2orCaCO3.Theporosityofthesorbentisincreasedbecauseofcalcinationandisdecreasedbecauseofsulfurization.InthecalcinationprocessH2OorCO2isescapedfromtheparticlesandporesareformedinparticles.ThereactionorconvertrateofCaOisinfluencedstronglybytheporestructurecharacters.FromCa(OH)2toCaOtheescapevelocityofH2Ooritsmasstransferisoneofthekeyfactorsinfluencingtheporeforming.Duringcalcinationprocessdifferentheatingvelocity,differentheatingtimeandtemperatureweresuggested.Thetemperaturerisingrateandcalciningtemperatureplayimportantroletotheporestructure.TheconvertratesofCaOobtainedthroughdifferentcalciningconditionswereinvestigatedexperimentally.SomeinterestingresultswereshowedthatthecalciumutilizationofCaOparticlesisdeterminednotonlybythespecialsurfaceareaandtotalporevolume,butalsobypore-sizedistribution.Themainfactorinfluencingthesulfationistheporediameterdistributionatlowersulfationtemperature.Forhigherreactiontemperaturespecificvolumeistheimportantreason.Butpore-sizedistributionisstronglyinfluencedbyheatfluxandtemperatureinthecalciningprocess.

  • 标签: 毛孔尺寸分布 氧化钙 杂质吸附剂 废气处理 二氧化硫
  • 简介:ChloridecontentandthepHvalueoftheporesolutionintheneighborhoodofsteelreinforcementaredecisiveparametersforinitiationandrateofcorrosion.Theporesolutionofcementmortarandhardenedcementpastehasbeenexpressedfromtheporespacebyhighpressureintheinvestigation.Theinfluenceofthewater-cementratio,age,andadditionofchloridetothefreshmixonchloridecontentintheporesolutionhasbeendeterminedbyionchromatography.AtthesametimethepHvalueoftheporesolutionhasbeendetermined.Thedissolvedchloridecontentdecreaseswithincreaseinthewater-cementratio.Theamountofboundchlorideincreaseswithtime,butitdecreaseswithdecreasingcontentofdissolvedchlorideintheporesolution.Asignificantinfluenceofcarbonationonthedissolvedchloridecontentoftheporesolutionhasbeenobserved.Withcompletecarbonation,thedissolvedchloridecontentincementmortarandhardenedcementpasteincreasesbyafactorbetween2and12.Theboundchloridedecreasesby27%-4%.Asexpected,thepHvaluedecreasesfromaround13.2toaslowas8.0duetocarbonation.ItcanbeconcludedthatcarbonationnotonlylowersthepHvaluebutliberatesboundchloride.Thisisoneobviousreasonwhythecombinedactionofchloridepenetrationandcarbonationacceleratessteelcorrosionandshortenstheservicelifeofreinforcedconcretestructures.

  • 标签: 英文摘要 编辑工作 优秀论文 医学期刊
  • 简介:有0.2–的直径的新宏观规模的SBA-15范围;0.5公里被sol–准备;胶化方法,tetrabutylorthosilicate(TBOS)在被用作硅来源和triblock共聚物和polyoxyethylene辛基酚醚(OP-10)(P123)被用作模板。结果球形的样品被XRD描绘,N2adsorption–;解吸附作用,TEM和SEM方法。结果证明SBA-15宏范围的内部结构有宏多孔的隧道(0.5μ;m)并且我酣睡的骨骼(4–;5nm)。有层次毛孔结构的这些SBA-15宏范围为Emodin分子表明高吸收能力。

  • 标签: 孔结构 表征 合成 三嵌段共聚物 溶胶凝胶法 聚氧乙烯醚
  • 简介:Adensityfunctionaltheoryisappliedtocalculatingthelocaldensityprofilesofcolloidsconfinedinaslit-likeporeaswellastheradialdistributionfunctionsofbulkcolloids.Theinteractionbetweenthecolloidalparticlesisdescribedusingahard-coreYukawamodel.TheexcessHelmholtzenergyfunctionalisacombinationofthemodifiedfundamentalmeasuretheoryofYuandWu(2002)forthehard-corecontributionandacorrectedmean-fieldtheoryfortheattractivecontribution.ComparisonwiththeresultsfromtheMonteCarlosimulationsshowsthatthecorrectedtheoryimprovesthedensityprofilesofcolloidsinthevicinityofcontactovertheoriginalmean-fieldtheory.Boththepresentcorrectedtheoryandsimulationssuggestthattherearedepletionanddesorptionforthecolloidwithstrongattractionbetweenparticlesatlowtemperature.

  • 标签: 胶体 斯裂孔 密度函数 非均匀流 Yukawa模型
  • 简介:Byutilizinghardtemplatemethodtoadjustthemesoporelength,andalkaliactivationtogeneratemicropores,twohierarchicalporouscarbons(HPCs)wereprepared.Withcontrollingoftheirmesoporelengthandtheactivationconditions,thecomplexsystemcomposedbyHPCsandelectrolytewassimplifiedandtheeffectofmesoporelengthontheperformanceofHPCsaselectrodesinsupercapacitorswasinvestigated.Itisfoundthatwiththemesoporelengthgettingsmaller,theorderedareagetssmallerandthaggregationoccurs,whichiscausedbythehighsurfaceenergyofsmallgrains.HPCwithlongpore(HPCL)exhibitsadonut-likemorphologywithwell-definedorderedmesoporesandaregularorientationwhileinHPCwithshortpores(HPCS),shortmesoporesareonlyorderlydistributedinsmallregionsLongerorderedchannelsformunobstructedwaysforionstransportintheparticleswhileshorterchannels,onlyorderlydistributedinsmallareas,resultsinblockedpaths,whichmayhindertheelectrolytionstransport.Duetotheunobstructedstructure,HPCLexhibitsgoodratecapabilitywithacapacitancretentionrateover86%ascurrentdensityincreasingfrom50mA/gto1000mA/g.ThespecificcapacitanceofHPCLderivedfromthecyclicvoltammetrytestat10mV/sisupto201.72F/g,whilethespecificapacitanceofHPCSisonly193.65F/g.

  • 标签:
  • 简介:Theactivatedaluminaasacatalystcarrierwerewidelyusedinautomotiveexhaustcatalystsunderhightemperature,suchas,petroleumrefiningcatalysts,hydrogenationandhydrodesulfurizationcatalystcarrierinChinaandabroad.γ-Al2O3wasthecatalystcarrierthatwasthemostwidelyusedandthebestcarrierofimprovedspecificsurfacearea.However,theactivationofthecoatingconsistedofγ-Al2O3wereusuallytransformedintoα-Al2O3at800oC,causingincreaseddensity,reducedspecificsurfacearea,andthecollapseresultofporestructure.Whilethetemperaturereached1200oC,activationofcoatingdetachedfromthecarrier,theresistanceofflowinggasincreased,catalyticactivitydecreased.AdditionofLa2O3stabilizedtheγ-Al2O3crystalstructure,whichwouldkeeptheactivationstabilityofcoatingatahightemperatureandinhibitactivityloss.Theactivatedaluminacarriertreatedwiththesolid-pore-expandingagentcontaining[La(EDTA)]-thatsynthesizedusingsolidandsolid-hybridapproachwiththethermalstabilizerlanthanaandEDTAatthehigh-temperaturehada10-30μmlargeporeporousnetwork-likestructure,afteraluminawascalcinedat1200oCfor1h.Thespecificsurfaceareaoffourspecimenwerebeyond120m2/g,whilethesamplespecificsurfaceareaofx([La(EDTA)]-)=1%wasupto150.36m2/g.

  • 标签: ALUMINA LANTHANA specific surface area thermal
  • 简介:Aseriesofregularwaveexperimentshavebeendoneinalarge-scalewaveflumetoinvestigatethewave-inducedporepressurearoundthesubmarineshallowlyembeddedpipelines.Themodelpipelinesareburiedinthreekindsofsoils,includinggravel,sandandsiltwithdifferentburialdepth.Theinputwaveschangewithheightandperiod.Theresultsshowthattheamplitudesofwave-inducedporepressureincreaseasthewaveperiodincrease,anddecayfromthesurfacetothebottomofseabed.Higherporepressuresarerecordedatthepipelinetopandthelowerporepressuresatthebottom,especiallyinthesandseabed.Thenormalizedpressurearoundpipelinedecreasesastherelativewaterdepth,burialdepthorscatteringparametersincrease.Forthesiltseabed,thewavelettransformhasbeensuccessfullyusedtoanalyzethesignalsofwave-inducedporepressure,andtheoscillatoryandresidualporepressurecanbeextractedbywaveletanalysis.Higheroscillatorypressuresarerecordedatthebottomandthelowerpressuresatthetopofthepipeline.However,higherresidualpressuresarerecordedatthetopandthelowerpressuresatthebottomofthepipeline.

  • 标签: 海洋工程 模拟技术 海底导管 项目研究
  • 简介:Porestructurecharacteristicsofrockareagreatconcernforresearchersandpractitionersinrockmechanicsandrockengineeringfields.Inthisstudy,mercuryintrusionporosimetry(MIP)wasusedtomeasureporesizedistribution,aswellasseveralimportantindexparametersofporestructure,forsevencommontypesofdeepsedimentaryrockswithatotaloffiftyrocksamples.Resultsshowasimilarporesizedistributionpatternoftherocksamplesinthesamelithologicalgroup,butremarkabledifferencesamongdifferentlithologicalgroups.Amongseveninvestigatedrocktypes,mudstonehasthesmallestporosityof3.37%,whileconglomeratehasthelargestvalueof18.8%.Itisalsofoundthattheporosityofrocktypeswithfinergrainsizeislowerthanthosewithcoarsergrainsize.Meanwhile,acomparisonoffrequencydistributionattenintervalsofpore-throatdiameteramongseventypesofsedimentaryrocksrevealsthatdifferentrocktypeshavedifferentdominantpore-sizeranges.Furthermore,permeabilityoftheinvestigatedsedimentaryrocksampleswasderivedbasedonMIPdatausingreportedtheoreticalequations.Amongsevenrocktypes,mudstonehasthelowestaveragedpermeability(3.64×10-6mD)whileconglomeratehasthehighestone(8.59×10-4mD).Frommudstonetoconglomerate,rockpermeabilityincreaseswithanincreaseofgrainsize,withonlyanexceptionofsiltstonewhichhasarelativelylargerporosityvalue.Finally,regressionanalysisshowthatthereisagoodfitting(R2=0.95)betweenpermeabilityandporositywhichcouldbeeasilyusedtoderivereliablepermeabilityvaluesofsimilarkindsofengineeringrocks.

  • 标签: 孔隙结构特征 平均渗透率 沉积岩 压汞法 深部 岩石类型
  • 简介:Aseriesofsisalbasedactivatedcarbonfiberswerepreparedwithsteamactivationattemperaturefrom750℃to900℃.Theirporestructureswerecharacterizedthroughtheirnitrogenadsorptionisothermsat77Kusingdifferenttheories.Theresultsshowedthatt-plotmethodandDR-plotmethodcouldsuitablybeusedtocharacterizethemesoporestructureandthemulti-stagedistributionofporesizeofactivatedcarbonfibers.Italsoshowedthattheporesizewidenswiththeincreaseofactivationtemperature.

  • 标签: 制备 活性炭纤维 吸附性能 放射性氙 核工业 废气净化
  • 简介:Porepresureindepboreholes:ItsmeasurementandrelationwithseismicactivitiesJIANLIGAO(高建理)SHIZONGSUN(孙世宗)JIANMINDING(丁健民)GU...

  • 标签: 丁健
  • 简介:ThemolecularsieveVPI-5wassynthesizedbyusingvariousorganicamines(DEA,Di-PA,DBA,DPenA,TBA,DEOAandTEOA)asthestructure-directingagent.TheuseofDPAenlargedtherangeofthecrystallizationtemperaturefrom110℃to190℃inthesynthesisofVPI-5,whiletheuseofTEOAchangedthecompositionofthereactantsinabroadvariety.DiaminesarethetypicalaminesinthesynthesisofVPI-5.AmongthemDBAandDPAarethemostfavoritestructure-directingagentsforthesynthesisofVPI-5molecularsieve.

  • 标签: VPI-5 MOLECULAR SIEVE AMINES
  • 简介:Centrifugeexperimentsarecarriedouttoinvestigatetheresponsesofsuctionbucketfoundationsunderhorizontaldynamicloading.Theeffectsofloadingamplitude,thesizeofthebucketandthestructuralweightonthedynamicresponsesareinvestigated.Itisshownthat,whentheloadingamplitudeisoveracriticalvalue,thesandattheupperpartaroundthebucketsoftensorevenliquefies.Theliquefactionindex(excessporepressuredividedbyinitialeffectivestress.Inthispaper,thedevelopmentaldegreeofexcessporepressureisdescribedbyliquefactionindex)decreasesfromtheupperparttothelowerpartofthesandfoundationintheverticaldirectionanddecreasesfromneartofarawayfromthebucket′ssidewallinthehorizontaldirection.Largesettlementsofthebucketandthesandaroundthebucketareinducedbythehorizontaldynamicloading.Thedynamicresponsesofthebucketofasmallerheight(whenthediameteristhesame)areheavier.Acycliccracksomedistancenearthebucketoccursinthesand.

  • 标签: 离心实验 抽水泵 水平动力载荷 海岸工程
  • 简介:Anumericalmethodisproposedfortheelasto-plasticityandpore-pressurecoupledanalysisonthepulloutbehaviorsofaplateanchor.Thebounding-surfaceplasticity(BSP)modelcombinedwithBiot’sconsolidationtheoryisemployedtosimulatethecyclicloadinginducedelasto-plasticdeformationofthesoilskeletonandtheaccompanyinggeneration/dissipationoftheexcessporewaterpressure.Thesuctionforcegeneratedaroundtheanchorduetothecyclicvariationoftheporewaterpressurehasmucheffectonthepulloutcapacityoftheplateanchor.Thecalculatedpulloutcapacitywiththeproposedmethod(i.e.,thecoupledanalysis)getslowerthanthatwiththeconventionaltotalstressanalysisforthecaseoflong-termsustainedloading,butslightlyhigherforthecaseofshort-termmonotonicloading.Thecyclicloadinginducedaccumulationofporewaterpressuremayresultinanobviousdecreaseofthestiffnessofthesoil-plateanchorsystem.

  • 标签: 弹塑性变形 行为分析 孔隙压力 锚固 钢板 超孔隙水压力
  • 简介:在那里躺在海床破坏和在碎的行动下面的毛孔水压力的分发之间的一种靠近的关系波浪。实验与泼出沙的海床学习常规碎波浪的1:30在波浪斜槽被执行导致的毛孔水压力。从常规波浪跑的大量大小被报导,包括波浪高度的时间系列,毛孔压力。录像记录被分析在打破区域的波浪测量海床形式的时间发展和沙的轨道的运动的特征。在断路器地区的毛孔水压力显示出包括波浪碎和讨厌的人繁殖取决于波浪阶段的时间变化。平均时间的毛孔水压力在海床表面附近是更高的。毛孔水压力的山峰价值在碎点显著地增加。在断路器地区的毛孔水压力差别力量的方向具有为对沉积动力学的正确描述的基本重要性。upwardsdirected压力差别可以由减少沉积的有效重量增加沙运输,从而增加床形式进化。在打破地区和一个沙酒吧的波浪极大地改变的海床配置显著地被产生。毛孔水压力的振幅随着海床表面变化了。结果是由于在泼出上打破常规波浪改进沙运输机制和海床回答的理解沙的床。

  • 标签: 孔隙水压力 配置文件 实验 波浪破碎区 沙质海床 时间序列
  • 简介:在Ziliujing形成的Daanzhai成员的紧密的石灰石的毛孔结构,侏罗记系统在中央四川盆,中国,对紧密的油的探索和发展复杂却必要。紧密的石灰石的毛孔结构被使用扫描电子学习显微镜学(SEM),氮吸附,高压的水银侵入,和原子磁性的回声(NMR)。试验性的结果建议毛孔主要是裂缝毛孔和mesopores和macropores贡献毛孔卷和特定的表面。排水量压力,平均毛孔尺寸,和有孔和渗透和罐头的同质系数相互关联被用来评估毛孔结构。完整的毛孔尺寸分发被联合氮吸附和高压的水银侵入获得。我们发现石灰石主要与250nm的直径包含mesopores。T2分发被变换成毛孔尺寸分发,很好匹配完整的毛孔尺寸分发。在T2和毛孔尺寸之间的关系与毛孔结构和罐头遵守一条幂定律和T2相互关联的几何平均数在毛孔结构评估被使用。

  • 标签: 紧密的油 石灰石 毛孔结构 氮吸附 水银侵入 原子磁性的回声